Indian Journal of Medical Microbiology

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    Asymptomatic SARS-COV-2 carriage and sero-positivity in high risk contacts of COVID-19 cases’
    (Indian Association of Medical Microbiologists, 2022-06) Das, Ayan Kumar; Chandra, Kailash; Dudeja, Mridu; Aalam, Mohd Khursheed
    Purpose: Identifying asymptomatic SARS-COV-2 carriage is one of the crucial factors in controlling the COVID 19 pandemic. The relationship between the asymptomatic viral carriage and the rate of seroconversion needs better understanding. The present study was conducted to identify the asymptomatic COVID-19 infection and seropositivity in high-risk contacts in the southern district of Delhi, India. Methods: Following the screening of 6961 subjects, a total of 407 asymptomatic high-risk subjects were selected. Demographic data, socioeconomic status, and history of COVID-19 related symptoms in the last 4 months were recorded. Blood samples and Nasopharyngeal/oropharyngeal swabs were collected for the detection of SARSCOV-2 RNA and anti-SARS-COV-2 antibodies. Results: 55 asymptomatic high-risk subjects (13.5%) tested positive for SARS-COV-2 infection and among them, 70.9% remained asymptomatic throughout their course of infection. The seropositivity among the subjects was 28.9% (n ¼ 118) and was found significantly higher among lower-middle socioeconomic strata (p ¼ 0.01). The antibody levels were significantly higher (p ¼ 0.033) in individuals with a previous history of COVID-19 like symptoms as compared to the subjects, who had no such history. Asymptomatic healthcare workers showed a significantly increased rate of SARS-COV-2 infection (p ¼ 0.004) and seropositivity (p ¼ 0.005) as compared to the non-healthcare workers. Subjects, who were exposed to infection at their workplace (non-hospital setting) had the least RT-PCR positivity rate (p ¼ 0.03). Conclusions: A large proportion of SARS-COV-2 infection remains completely asymptomatic. The rate of asymptomatic carriage and seropositivity is significantly higher in healthcare workers as compared to the general population. The level of SARS-COV-2 antibodies is directly related to the appearance of symptoms. These observations may contribute to redefining COVID 19 screening, infection control, and professional health practice strategies.
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    Anaerobes in cardiac infections: A decade experience from the tertiary care center
    (Indian Association of Medical Microbiologists, 2022-06) SaiKiran, K.V.P.; Biswal, Debasish; Agrawal, Sonu Kumari; Batra, Priyam; Sagar, Tanu; Choudhary, S.K.; Verma, Nishant; Chaudhry, Rama
    Purpose: Anaerobic infections are common yet life-threatening. They are being recovered from all sites of the body, including the cardiovascular system. This study was aimed to determine the retrospective analysis on the isolation of anaerobes in cardiovascular samples received for a decade-long duration. It helps in knowing the frequency of isolation of anaerobic causes of cardiovascular infection. Methods: All cardiovascular samples from the department of Cardio-thoracic vascular surgery from January 2010 to December 2020 were studied. Results: Of 601 samples received, predominant samples were vegetations and valvular tissues of 258, followed by 98 samples of pericardial tissues, 92 samples of embolus, 90 samples of blood and post-operative collections, and 63 excised aneurysms and vascular grafts. Of the total, 15 samples grew anaerobes where Clostridium species were the predominant isolates. Clostridioides difficile was isolated in 2 samples. Conclusions: Anaerobes in cardiovascular samples are uncommon yet form a significant cause of morbidity and mortality. Most infections are from the contiguous spread, penetrating trauma, and hematogenous causing endocarditis or valvular infections. These conditions and samples form the seat of infectious focus and clinical suspicion towards the anaerobic cause of these conditions, especially in conventional routine culture-negative samples. Timely diagnosis of anaerobic infections plays a vital role in the good prognostic outcome of patients undergoing cardiothoracic and vascular surgery.
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    Presence of diarrhea associated with better outcomes in patients with COVID-19 – A prospective evaluation
    (Indian Association of Medical Microbiologists, 2022-09) Singh, Seerat; Samanta, Jayanta; Suri, Vikas; Bhalla, Ashish; Puri, Goverdhan Dutt; Sehgal, Rakesh; Kochhar, Rakesh
    Purpose: Gastrointestinal (GI) manifestations have been well documented in patients with coronavirus disease 2019 (COVID-19), but its clinical impact on the course of the disease is debatable. Majority of the available data is retrospective, and hence this prospective study was planned to study the impact of GI symptoms on COVID-19 outcome. Methods: All COVID-19 patients admitted in a tertiary care centre from August–October 2020 were screened and patients without pre-existing GI diseases were included. A detailed history of the various symptoms including duration was documented. Various baseline laboratory investigations and inflammatory markers were conducted as per the protocol. Patients with and without diarrhea were compared for the various disease outcome parameters. Results: Of the 244 patients screened, 203 patients (128 males; 63.1%) were included. Respiratory symptoms alone were present in 49 (24.1%), GI symptoms alone in 20 (9.9%) and 117 (57.6%) had both. Overall GI symptoms was noted in 137 (67.5%) cases with the commonest being diarrhea (61; 30.0%). Patients with both respiratory and any GI symptoms showed a lower trend towards need for mechanical ventilation (12.2% vs 7.7%; p ¼ 0.35) and mortality (10.2% vs 4.3%; p ¼ 0.14) compared to respiratory symptoms alone, although not statistically significant. Patients with diarrhea (n ¼ 61) had no mortality (0% vs 7.7%; p ¼ 0.036) or need for mechanical ventilation and shorter hospital stay compared to those who did not have diarrhea. Conclusion: GI symptoms are frequent in patients with SARS-CoV-2 infection and the commonest is diarrhea. Diarrhea is a harbinger of better outcome with lower mortality among COVID-19 positive patients.
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    Campylobacter diarrhea in children in South Asia: A systematic review
    (Indian Association of Medical Microbiologists, 2022-09) Murugesan, Malathi; Abraham, Dilip; Samuel, Prasanna; Ajjampur, Sitara SR
    Background: Campylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries. Methods: This systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations. Results: Of the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli. Conclusion: In South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools.
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    Impact of B.1.617 and RBD SARS-CoV-2 variants on vaccine efficacy: An in-silico approach
    (Indian Association of Medical Microbiologists, 2022-09) Ranjan, Prashant; Neha; Devi, Chandra; Jain, Garima; Mallick, Chandana Basu; Das, Parimal
    Purpose: The existing panels of COVID-19 vaccines are based on the spike protein of an earlier SARS-CoV-2 strain that emerged in Wuhan, China. However, the evolving nature of SARS-CoV-2 has resulted in the emergence of new variants, thereby posing a greater challenge in the management of the disease. India faced a deadlier second wave of infections very recently, and genomic surveillance revealed that the B.1.617 variant and its sublineages are responsible for the majority of the cases. Hence, it's crucial to determine if the current vaccines available can be effective against these variants. Methods: To address this, we performed molecular dynamics (MD) simulation on B.1.617 along with K417G variants and other RBD variants. We studied structural alteration of the spike protein and factors affecting antibody neutralization and immune escape via In silico docking. Results: We found that in seven of the 12 variants studied, there was a structural alteration in the RBD region, further affecting its stability and function. Docking analysis of RBD variants and wild-type strains revealed that these variants have a higher affinity for the ACE2 (angiotensin 2 altered enzymes) receptor. Molecular interaction with CR3022 antibody revealed that binding affinity was less in comparison to wild type, with B.1.617 showing the least binding affinity. Conclusions: The results of the extensive simulations provide novel mechanistic insights into the conformational dynamics and improve our understanding of the enhanced properties of these variants in terms of infectivity, transmissibility, neutralization potential, virulence, and host-viral replication fitness.
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    Seropositivity of Anti-SARS CoV2 IgG antibodies in health care workers of an Indian tertiary care hospital during COVID-19
    (Indian Association of Medical Microbiologists, 2022-06) Verma, Anuragani; Shukla, Suruchi; Verma, Anil K.; Puri, Bipin; Jain, Amita
    Purpose: Health care workers [HCW] are at a higher risk of infection SARS CoV2 infection due to frequent and close contact to patients with COVID-19. Methods: Serum samples from 500 HCW's were tested for SARS CoV2 IgG antibodies in October 2020. A questionnaire was used to collect demographic and clinical data. All these HCWs were tested for COVID-19, in 2nd week of September 2020, as a hospital policy. Results: Anti SARS CoV2 antibodies were detected in 128/ 500 [25.6%] HCWs. A total of 195/ 500 [39%] enrolled cases had already tested positive for Covid-19 at least once in last six months by RT-PCR. Sixty eight percent of HCWs with previous COVID-19 positivity by RT- PCR tested positive for Anti SARS CoV2 antibodies, whereas only 2.76% of asymptomatic HCWs tested positive. Of 121 anti SARS-CoV-2 IgG positive persons, 70 [57.85%] had CT value < 25. Low CT value and asymptomatic cases had a strong reverse statistically significant association with SARS CoV2 IgG antibody positivity. Conclusions: We report that sero-conversion rate in HCWs is similar to that in general population suggesting that preventive practices used in hospitals are satisfactory. Cases with low viral counts in respiratory sample and asymptomatic cases have lower rate of seroconversion.
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    LDBio Aspergillus immunochromatographic test lateral flow assay for IgG/IgM antibody detection in chronic pulmonary aspergillosis: Single-centre evaluation and meta-analysis
    (Indian Association of Medical Microbiologists, 2022-06) Singh, Shreya; Choudhary, Hansraj; Agnihotri, Sourav; Sehgal, Inderpaul Singh; Agarwal, Ritesh; Kaur, Harsimran; Ghosh, Anup; Chakrabarti, Arunaloke; Rudramurthy, Shivaprakash M.
    Purpose: Chronic pulmonary aspergillosis (CPA) is an infection of the lung usually caused by Aspergillus fumigatus in patients with pre-existing pulmonary diseases. Its diagnosis hinges on demonstrating IgG antibodies against A. fumigatus. Herein, we evaluated the performance of a newly introduced point of care test (POCT) kit, the LDBio Aspergillus IgG/IgM lateral flow assay (LFA) in India with the standard ImmunoCAP kit for diagnosing CPA. Methods: A total of 60 serum samples (30 CPA cases and 30 controls) were evaluated by the Aspergillus immunochromatographic test (ICT) IgG/IgM LFA. Fluorescent-enzyme immunoassay was used to determine specific A. fumigatus-IgG concentrations (positive >27 mgA/L). Further, a systematic review and meta-analysis of studies (up to August 26, 2021) reporting the performance of LDBio ICT for the diagnosis of CPA was performed. Result: A sensitivity of 86.7%, specificity of 90%, negative predictive value of 87.1%, positive predictive value of 89.7%, negative likelihood ratio of 0.15, positive likelihood ratio of 8.67, and was observed for the LDBio IC. There was good agreement between LDBio ICT and ImmunoCAP (88.3%) with a Cohen's Kappa score of 0.77. Our systematic review identified four studies and the pooled sensitivity of 90%, specificity of 91%, area under the curve of 0.94 and diagnostic odds ratio of 57.2, for CPA diagnosis by LDBio ICT. Conclusion: Aspergillus LDBio ICT assay exhibits good sensitivity and can be used to screen CPA cases
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    Vaccines and vaccine resistance: Past, present and future
    (Indian Association of Medical Microbiologists, 2022-06) Khardori, Nancy
    Background: Edward Jenner, by any definition would be considered the father of vaccinology. His use of cow pox virus for vaccinating against small pox is the prime example of a live vaccine. Using a virus that has very low virulence for humans and therefore, fits the definition of attenuated. Hesitancy towards a vaccine of this type, much before the science of microbiology and immunology were established, would have been justifiable. In the first half of 20th century, large number of vaccines became available for childhood diseases with significant morbidity and mortality. Around the same time global travel and trade led to escalation in the widespread transmission of diseases caused by microbes. Objective: The objective of this narrative is to offer a balanced view of science behind vaccines, their current status and advances expected in the near future. At the same time the various types of reactions from public at large towards vaccines over past decades are reviewed. Content: This narrative provides a historical perspective of vaccine development, reviews mechanisms of vaccine induced protection, currently available vaccine technologies and vaccines. The focus is on newer vaccines including those utilizing viral vectors and gene based vaccines. Based on the times during which this narrative is being written, messenger RNA vaccines are discussed in detail. Conclusion: The content and review of literature offered in this review makes the impact of vaccines on human life clear. It is also to be accepted that resistance and hesitation towards vaccines is nothing new or limited to vaccines being used during the ongoing pandemic of Covid 19. The continued development of science and products of vaccinology is necessary for further impact on human life. The development of a strong public health infrastructure by nations around the world is the key to improve upon current efforts at public awareness, proactive interventions and appropriate vaccine utilization during all times. Preparedness for epidemics and pandemics would then become more and more efficient than currently in existence.
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    Susceptibility testing for aztreonam plus ceftazidime/avibactam combination: A general guidance for clinical microbiology laboratories in India
    (Indian Association of Medical Microbiologists, 2022-03) Bakthavatchalam, Yamuna Devi; Walia, Kamini; Veeraraghavan, Balaji
    Metallo beta-lactamases-producing Gram-negative infection is often challenging and there is no defined treatment option. In recent years, the combination of aztreonam with ceftazidime-avibactam has gained much clinical attention mainly for MBL-producing Enterobacterales, while MBL-producing P. aeruginosa and A. baumannii are likely to be resistant. A consensus susceptibility testing method for this triple combination has yet to be recommended. Various methods such as broth disk elution, disk stacking, gradient strip stacking, and strip crossing have been proposed for testing this combination. Among them, broth disk elution and strip based testing methods showed good correlation with the broth micro-dilution method.
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    Study of immunogenicity, safety and efficacy of covishield vaccine among health care workers in a tertiary cardiac care centre
    (Indian Association of Medical Microbiologists, 2022-06) Mahadevaiah, Ashwini; Doddamadaiah, Chaithra; K S, Sadananda; Nanjappa, Manjunath Cholenahalli
    Purpose: The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might be curtailed by vaccination. We assessed the safety, and immunogenicity of Covishield vaccine among Health care workers (HCWs) in a tertiary cardiac care centre. Methods: It's a prospective analytical study, conducted at Sri Jayadeva Institute of cardiovascular science and research centre, Mysore, between January 2021 to May 2021. Pre and Post vaccination SARS CoV2 IgG antibodies were assessed among 122 HCWs. Interval between two doses in this study were 4 and 6 weeks. Adverse events following immunisation b(AEFI) and efficacy were assessed and followed up for two month post vaccination. Results: Post vaccination seropositivity was 69.67% in overall study participants. Seropositivity and P/N ratio median value in uninfected and infected group were 60.43% (n ¼ 55),3.47 (IQR: 2.56–5.22) and 96.77% (n ¼ 30),9.49 (IQR: 7.57–12.30) respectively (P < 0.001). Seropositivity and P/N ratio after 4 and 6 weeks were 48.3% (n ¼ 60), 2.95 (IQR: 1.91–4.24), and 83.8% (n ¼ 31), 4.88, (IQR: 3.39–6.43) respectively (P < 0.001). AEFI after first and second dose was 72.9% and 27.8% (p < 0.05) respectively. The most common symptoms after both doses of vaccination were local pain (73% & 88.2%), followed by fever (38.2% & 26.5%). The average duration of symptoms in both doses was 1.75 days. Of 122 participants only 10 (8.19%) had breakthrough infection after two doses of vaccination with mild severity. Conclusion: Covishield vaccine has showed seropositivity of 69.67%.It has acceptable level of safety profile. Seropositivity and P/N ratio has increased with increase in interval between two doses. Though it has not prevented breakthrough infection it has certainly reduced the severity of infection.
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    Detection and molecular typing of campylobacter isolates from human and animal faeces in coastal belt of Odisha, India
    (Indian Association of Medical Microbiologists, 2019-09) Mohakud, NK; Patra, SD; Kumar, S; Sahu, PS; Misra, N; Shrivastava, AK
    Introduction: Campylobacter-mediated diarrhoea is one of the major causes of gastroenteritis globally. A majority of the Campylobacter spp. that cause disease in humans have been isolated from animals. Faecal contamination of food and water is the identified frequent cause of human campylobacteriosis. Methodology: In the present study, faecal samples from patients with symptoms of acute diarrhoea (n = 310) and domestic animals including cows (n = 60), sheep (n = 45) and goats (n = 45) were collected from the same localities in the peri-urban Bhubaneswar city. Genomic DNA isolation followed by polymerase chain reaction and sequencing was employed to analyse Campylobacter spp.-positive samples. Results: Of the 460 faecal samples, 16.77% of human samples and 25.33% of animal samples were found to be positive for Campylobacter spp. Among animals, the isolation rate was highest in sheep followed by cows and goats with 9.33%, 8.66% and 7.33%, respectively. The highest number of Campylobacter-positive cases was diagnosed in infants of 2–5 years age. Concurrent infection of other pathogens in addition to Campylobacter spp. was frequently detected in the samples. Conclusion: The present study showed the incidence of Campylobacter infections in human and different animal species in and around Bhubaneswar, Odisha. The analysis suggested that domestic animals can be the potential sources for human campylobacteriosis in the region.
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    Geographically distinct North-East Indian Helicobacter pylori strains are highly sensitive to clarithromycin but are levofloxacin resistant
    (Indian Association of Medical Microbiologists, 2019-09) Mahant, S; Sharma, AK; Gehlot, V; Mukhopadhyay, AK; Chhawchharia, A; Dutta, S; Agarwal, A; Som, A; Das, K; Das, R
    Purpose: Helicobacter pylori causes various gastro-intestinal diseases. Antibiotic resistance to commonly used antibiotics for the treatment of H. pylori infection is the major cause for treatment failure. The aim of this study is to determine the antimicrobial susceptibility pattern for clarithromycin and levofloxacin and find the evolutionary relationship of the partial sequence of 23S rRNA and gyraseA gene of H. pylori by phylogenetic analysis. Materials and Methods: A total of 46 H. pylori strains were tested for clarithromycin and levofloxacin susceptibility pattern and phylogenetic tree were reconstructed by PhyML software. Results: In this study, we observed that only 6.5% of North-East Indian H. pylori strains were resistant for clarithromycin showing mutation at A2143G and T2182C positions of 23S rRNA gene. Resistance for levofloxacin was observed in 89.1% of the H. pylori strains showing mutations at asparagine to lysine at 87 and aspartic acid to glycine/tyrosine/asparagine at 91 positions of gyraseA gene. The phylogenetic tree of the partial sequence of 23S rRNA and gyraseA gene depicts that the North-East Indian strains falls in different cluster when compared to other countries. Conclusions: Resistance for clarithromycin was less in North-East Indian strains but high for levofloxacin indicating that first-line therapy may be best and effective for eradication of H. pylori in this region. This study is the first report that showed antibiotic susceptibility pattern for clarithromycin and levofloxacin by mutation analysis. By partial sequencing of 23s rRNA and gyraseA gene, we found that North-East Indian strains are geographically distinct.
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    Protocol for developing a surveillance system for surgical site infections
    (Indian Association of Medical Microbiologists, 2019-09) Mathur, P; Mittal, S; Trikha, V; Lohiya, A; Khurana, S; Katyal, S; Bhardwaj, N; Sagar, S; Kumar, S; Malhotra, R; Walia, K
    Purpose: Healthcare-associated infections (HCAIs/ HAIs) are the most common adverse occurrences during health care delivery. Across the globe, millions of patients are affected by HAIs annually, with a higher burden and impact in developing nations. a major lacuna in planning preventing protocols is the absence of National Surveillance Systems in most low-middle income countries, which also prevents allocation of resources to the high-priority areas. Among all the HAIs, there is a huge global burden of SSIs, in terms of morbidity, prolonged hospital stays, increased antimicrobial treatment as well as attributable mortality. Method: This manuscript details the process of establishment of an SSI surveillance protocol at a level-1 trauma centre in North India. Result and Conclusion: Surveillance is an essential tool to reduce this burden. It is also an important primary step in recognizing problems and priorities, and it plays a crucial role in identifying risk factors for SSI and to be able to target modifiable risk factors. Therefore, it is imperative to establish reliable systems for surveillance of HAIs, to regularly estimate the actual burden of HAIs, and to use these data for developing indigenous preventive measures, tailored to the country's priorities.
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    Erratum: Abstracts - Indian journal of medical microbiology - supplement 1 - 2019 - Volume 37
    (Indian Association of Medical Microbiologists, 2019-09)
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    Seroprevalence of Toxoplasmosis at a Tertiary Care Centre in North India from 2004 to 2014
    (Indian Association of Medical Microbiologists, 2019-09) Mewara, A; Singh, S; Khurana, S; Gupta, P; Sehgal, R
    Purpose: This study was carried out to determine the seroprevalence of anti-Toxoplasma gondii antibodies in different groups of patients at a tertiary care hospital in North India. Materials and Methods: Clinical and demographic data such as age and gender of patients who had undergone testing for the presence of anti-T. gondii IgG and IgM antibodies between January 2004 and October 2014 were retrospectively analysed. Results: Amongst the 8397 serum samples, an overall seropositivity of 21% (n = 1763) and IgG and IgM seropositivity of 5.7% (n = 481) and 15.3% (n = 1282) were respectively observed. Compared to the period of 2004–2012 (median seroprevalence: 23.6%), a decline in seropositivity to 9.7% in 2013 and 8.1% in 2014 was noted. A rising seroprevalence with age and a higher seroprevalence in females versus males (29.5%, n = 1179 vs. 13.3%, n = 584) were recorded. The highest seroprevalence was observed in suspected ocular toxoplasmosis (47.2%, n = 47), followed by neurological (26.8%, n = 77), human immunodeficiency virus/acquired immunodeficiency syndrome (18.9%, n = 267), post-transplant (17.1%, n = 12) and congenital (7.2%, n = 144) toxoplasmosis. In patients screened for Toxoplasma exposure, the seropositivity was 47.8% (n = 11) in transplant screening and 44.9% (n = 781) in antenatal screening. Conclusion: Toxoplasma infection is highly prevalent in the population of North India across various clinical categories of patients. Future studies focusing on continuous monitoring of seroprevalence trends and elucidation of the risk factors associated with seropositivity in more defined groups of patients are needed.
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    Clonal clusters and virulence factors of methicillin-resistant Staphylococcus Aureus: Evidence for community-acquired methicillin-resistant Staphylococcus Aureus infiltration into hospital settings in Chennai, South India
    (Indian Association of Medical Microbiologists, 2019-09) Abimannan, N; Sumathi, G; Krishnarajasekhar, O R; Sinha, B; Krishnan, P
    Background and Objective: Staphylococcus aureus is one of the major pathogens of nosocomial infections as wells as community-acquired (CA) infections worldwide. So far, large-scale comprehensive molecular and epidemiological characterisation of S. aureus from very diverse settings has not been carried out in India. The objective of this study is to evaluate the molecular, epidemiological and virulence characteristics of S. aureus in both community and hospital settings in Chennai, southern India. Methods: S. aureus isolates were obtained from four different groups (a) healthy individuals from closed community settings, (b) inpatients from hospitals, (c) outpatients from hospitals, representing isolates of hospital–community interface and (d) HIV-infected patients to define isolates associated with the immunocompromised. Antibiotic susceptibility testing, multiplex polymerase chain reactions for detection of virulence and resistance determinants, molecular typing including Staphylococcal cassette chromosome mec (SCCmec) and agr typing, were carried out. Sequencing-based typing was done using spa and multilocus sequence typing (MLST) methods. Clonal complexes (CC) of hospital and CA methicillin-resistant S. aureus (MRSA) were identified and compared for virulence and resistance. Results and Conclusion: A total of 769 isolates of S. aureus isolates were studied. The prevalence of MRSA was found to be 7.17%, 81.67%, 58.33% and 22.85% for groups a, b, c and d, respectively. Of the four SCCmec types (I, III, IV and V) detected, SCCmec V was found to be predominant. Panton-Valentine leucocidin toxin genes were detected among MRSA isolates harbouring SCCmec IV and V. A total of 78 spa types were detected, t657 being the most prevalent. 13 MLST types belonging to 9 CC were detected. CC1 (ST-772, ST-1) and CC8 (ST238, ST368 and ST1208) were found to be predominant among MRSA. CA-MRSA isolates with SCCmec IV and V were isolated from all study groups including hospitalised patients and were found to be similar by molecular tools. This shows that CA MRSA has probably infiltrated into the hospital settings.
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    Cross-country transport and isolation and identification of Streptococcus pneumoniae by use of alternate sources of blood supplemented media among laboratories in India
    (Indian Association of Medical Microbiologists, 2019-09) Amarnath, SK; Joshi, S; Abhyankar, MN; Adhikary, R; Beena, H B; Chugh, T D; Gandhi, K D; Hittinahalli, V; Indumathi, V A; Rajavari, M; Muralidharan, S; Rao, S S; Roy, I; Saini, N
    Background: The isolation of S. pneumoniae (Sp) depends on specimen integrity / transport, media and expertise. The non-availability of sheep blood agar poses a challenge in identification of colonial morphology and identification in India. Methods: Laboratories processed swabs containing either pure Sp or Sp in mixed cultures with a second (confounding) bacterium shipped across the country in cold conditions. Duplicate set of swabs was shipped back to the central laboratory to assess the impact of shipping on culture viability. The identical swab was cultured on sheep, human blood and one additional agar plate used in the laboratory. Results: 46/60(77%) of cultures containing only Sp were correctly identified. In specimens where Sp was present in mixed culture, the proportion of isolates in which Sp was correctly identified varied, with most variability attributed to the particular confounding organism rather than the media. There was no discernible impact of temperature-controlled (4-6°C) transport on the isolation of Sp from culture swabs. Conclusions: The study clearly elucidates the ability of laboratories for isolation of S. pneumoniae on human blood agar in resource limited settings. The results highlight the difficulties inherent in correctly identifying pathogens in mixed cultures in needs improvement using standardized tests across the study centers. The study also reaffirms the ability to transport biological specimens over long geographical distances without loss.
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    Clonal similarities and sequence-type diversity of invasive and carriage Streptococcus pneumoniae in India among children under 5 Years
    (Indian Association of Medical Microbiologists, 2019-09) Varghese, R; Neeravi, A; Subramanian, N; Pavithra, B; Kavipriya, A; Kumar, JL; Girish, Kumar, C, P; Jeyraman, Y; Karthik, G; Verghese, VP; Veeraraghavan, B
    Background: Pneumococcal pneumonia is one of the major causes of mortality in children less than 5 years in Asia, especially in India. Available PCVs have less serotype coverage in India compared to western countries. Moreover, the baseline pneumococcal serotype and sequence type data is limited and available data doesn't represent the entire India. With this background we aimed to characterize invasive and carriage isolates of S. pneumoniae from a tertiary care hospital in South India. Materials and Methods: A total of 221 S. pneumoniae isolates, invasive (n=138) and carriage (n=83) between the time period of 2012-2018 were included. Isolates was identified and confirmed using standard laboratory protocols. Serotyping was performed by Customized sequential multiplex PCR and MLST as described in www.pubmlst.org. Results: The major serotypes were 19F, 6B, 14, 6A and 19A and the sequence types (ST) were ST63, 236 and 230. Predominant STs in invasive was ST 63 whereas in carriage were ST4894 and 1701. High level ST diversity in carriage was observed. Majority of the STs were SLVs or DLVs of previously reported STs or PMEN clones. Phylogenetic analyses of the STs revealed gradual expansion of three PMEN CCs CC320, 63 and 230. Conclusion: The vaccine serotypes were the predominant ones found to be associated with IPD, PMEN clones, new STs and antimicrobial resistance. Accordingly, PCV13 is expected to provide invasive serotype coverage of 75% in Indian children less than 5 years. This study provides baseline serotype and sequence type data prior to the introduction of PCV in South India.
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    Seroprevalence of brucellosis in Western Rajasthan: A study from a tertiary care centre
    (Indian Association of Medical Microbiologists, 2019-09) Bansal, Y; Aggarwal, A; Gadepalli, R; Nag, VL
    Brucellosis is a significant bacterial zoonotic disease with a high seroprevalence in low-to-middle-income countries where there is a significant contact of humans with animals. This prospective study was conducted to observe the seroprevalence of brucellosis in 75 symptomatic patients with pyrexia of unknown origin (PUO) and 75 high-risk individuals (10 veterinarians, 15 milkmen and 50 healthy contacts of symptomatic patients) with possible exposure to brucellosis. Serum samples collected from these patients and individuals were subjected to rose Bengal test (RBT) and ELISA for the detection of IgM and IgG antibodies. RBT was positive in 50 samples (40 PUO and 10 high risk), of which 25 (33.3%) PUO cases had detectable IgM antibodies, whereas IgG antibodies were detected in 20 patients. None of samples from high-risk individuals was reactive for IgM/IgG antibodies by ELISA. The overall seroprevalence in this study was 16.7% (33.3% in PUO patients). Being a predominantly livestock rearing area, brucellosis is a significant health-care problem in this part of India with this entity being linked to 33% of PUO cases.
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    Utility of QuantiFERON®-TB gold In-Tube test compared with tuberculin skin test in diagnosing tuberculosis in Indian children with malnutrition
    (Indian Association of Medical Microbiologists, 2019-09) Boddu, D; Verghese, VP; Michael, JS; Chacko, A; Jeyaseelan, V
    This prospective cohort study was conducted to compare the accuracy of QuantiFERON®-TB (QFT) Gold In-Tube test and tuberculin skin test (TST) in diagnosing tuberculosis (TB) in predominantly bacille Calmette–Guerin-vaccinated children with a high incidence of malnutrition. The sensitivity of the QFT versus the TST was 69.6% versus 52.9% for WHO-defined TB, with specificity of 86% versus 78.3%, respectively. The concordance of the TST and QFT was 79% overall (? = 0.430), 62.5% in those with WHO-defined TB and 85.7% in those without TB. Majority of the QFT+/TST ? discordance was seen in children with TB, whereas majority of the TST+/QFT ? discordance was seen in those without TB. The TST was more likely to be negative in children with moderate-to-severe malnutrition (P = 0.003) compared to the QFT, which was more likely to be positive in younger children. The significantly better performance of the QFT in malnourished children and those at younger ages supports its use for TB diagnosis in these subpopulations.